Polynomial Checking
Adds 1 or more characters to the end of message (based on a mathematical algorithm)
Two types: Checksum and CRC
Checksum
- Calculated by adding decimal values of each character in the message,
- Dividing the total by 255. and
- Saving the remainder (1 byte value) and using it as the checksum
- 95% effective
Cyclic Redundancy Check (CRC)
- Computed by calculating the remainder to a division problem: